Storage pests of agriculture

1. SECONDARY STORAGE PESTS
Jyotismita Saikia
Msc, 2nd year
University of Mysore, Karnataka,

2. Contents
 What is storage pest
 Classification of storage pests
 Primary
 Secondary
 Secondary
 Description and damage symptoms
 Management strategies
 Summary
 References.

3. What is storage pest ?
 A pest is an organism that cause nuisance to animal and
human welfare.
 A storage pest is an insect or other animal that damages or
A storage pest is an insect or other animal that damages or
destroys stored food or other stored valuable organic
matter.
 Storage pests often go unnoticed because they infest items
that are not regularly used and they may be very small in size.

5. Classification of storage pest
Storage grain pests are classified into two types
 Primary storage pest
 Secondary storage pest.
 Secondary storage pest.
 Insects considered as primary pests of stored products
cause damage to stored grains by directly feeding on
the grain at some point in their lifecycle.

6. Secondary storage pests
 Secondary grain insects feed on broken grain and any powder
products left as a result of the broken grain.
 Secondary pests attack only damaged grain, dust and milled
products.
products.

7. Common name Pest Family Order
Saw toothed grain beetle Oryzaephilus surinamensis Cucujidae: Coleoptera
Long headed flour beetle Latheticus oryzae Tenebrionidae Coleoptera
Flat grain beetle Cryptolestus minutas Cucujidae Coleptera
Flat grain beetle Cryptolestus minutas Cucujidae Coleptera
Grain mite Acarus siro --- Acarina
Rice moth Corcyra cephalonica Pyrallidae Lepidoptera

8. Saw toothed grain beetle
Scientific name: Oryzaephilus surinamensis
Order: Coleoptera
Family: Cucujidae
 Host range: Rice, wheat, maize, cereal products, oil seeds and dry
fruits.
 Distribution :Worldwide
 Pest status: Important pest of a wide range of stored products of plant
or animal origin

9. Description and life history
It is slender, dark, narrow, flattened beetle having a row of saw like sharp teeth on each side
of the prothorax. The antenna is clubbed and elytra cover abdomen completely.
 Fecundity: 300/gravid female
 Hatching period : 3 -17 days.
 Larval period: 14- 20 days.
 Pupal period : 7-21 days.
 Duration of life cycle is highly dependent on temperatures, and takes 3-4 weeks at
temperatures above 30˚C; longer during cooler months. 5-6 generations are possible in a
year.

10. Damage symptoms
 Feeding on germ region of stored seeds is reported to reduce
germination.
 Adult beetles and grubs bore through the stored product, and leaving
 Adult beetles and grubs bore through the stored product, and leaving
holes and ultimately reducing it to a fine powder.
 Adult beetles readily chew through plastic and paper packaging to reach
food sources.
 Heavy infestations can cause stored products to heat up leading to mold
growth, and reduction in flavor and quality of food items.

11. Long headed flour beetle
• Scientific name: Latheticus oryzae
Order: Coleoptera
Family:Tenebrionidae
 Distribution: Worldwide
 Pest status: Important pest of a wide range of stored grains and their products such as
 Pest status: Important pest of a wide range of stored grains and their products such as
cereals and flour.
Description of the pest
 The beetle is light brown in colour with elongated body, measuring 2 -3 mm in
length.
 Resembles to Tribolium

12. Life cycle
 Fecundity: 400
 Incubation period: 7-12 days
 Larval period: 15-80 days
 Pupal period: 5-10 days
Damage symptoms
Grub
Damage symptoms
 Both grubs and adult beetles feed on the milled
products. It occurs as secondary infestation in stored
grain.
 It attacks cereal flour, packaged food, rice and rice
products. Occurs as secondary infestation in stored
sorghum, wheat, etc. Adult

13. Flat grain beetle
Scientific name: Cryptolestes minutes
Order: Coleoptera
Family: Cucujidae
 Distribution: Worldwide
 Status of the pest: Important pest of a wide range of stored grains and their products such as
 Status of the pest: Important pest of a wide range of stored grains and their products such as
cereals and flour.
 Host range: Cereal flours, packaged food, rice and rice products, grains with excessive dust,
dockage and broken grains with high moisture contents preferred.
Description and life history
 It is smallest among the stored grain insect pests.
 It is light to dark reddish brown beetle measuring 1.5 mm to 2.0 mm.

14. Life cycle of the pest
 It lays white eggs loosely in flour, grain or crevices. The egg period is 5 days.
 The larva is cigar like yellowish white with two reddish brown spots at anal segment.
The larval period is 21 days. It pupates in a gelatinous cocoon.
 The life cycle is completed in 42 days.
Damage symptoms
 Both grubs and adults feed on broken grains or on milled products. In case
of heavy infestation it cause heating in grain and flour.
 It attacks rice, maize, wheat with excessive broken, different flours, ground
nut particularly with high moistures and mouldy grains

15. Grain mite
Scientific name: Acarus siro
Order:Acarina
Family: Acaridae
• Distribution:Worldwide
• Pest status: Occasional pest
Description of the pest
 It is pale straw to dark reddish brown mite .
 Tiny, microscopic arthropods with eight legs, about 1⁄2 inch or lesser in
length.

16. Life cycle
 Fecundity: 100 eggs/female
 Larval instars: 1-3
 Total life cycle : 9-12 days
Damage symptoms :
Damage symptoms :
 It feeds on the surface of the grains.
 It attacks cereal grains, flour and other eatables.
 In severe infestations, the mites can be seen as a layer of fine powder over the host
 Material and they give off a ‘minty’ or similar sweet-sickly odour when crushed.
 This renders food material unsuitable for consumption.

17. Rice moth
 Scientific name: Corcyra cephalonica
Order: Lepidoptera
Family: Pyralidae
 Host range: Rice, jowar, other millets, whole cereals, cereal products, pulses,
processed products of cereals, pulses, oil seeds, nuts, dry fruits and milled spices.
Symptoms of damage
 Larva is only responsible for damage.
 It contaminates food grains with frass, moults and dense webbing.
 In whole grains, kernels are bound into lumps upto 2 kg.

18. Larva of rice moth
Rice moth Adult

19. Fig or Almond Moth
Scientific name: Ephestia cautella
 Host range: Wheat, rice, maize, jowar, groundnuts,
spices.
Symptoms of damage
 Larva feeds on germ portion leaving the rest of the
kernel undamaged.
 In bulk infestation its damage is limited to peripheral
top layers only.
 Web formation covers the bags, floor-space and mill
machinery thereby leading to clogging in mills.
Larva
Adult

20. Secondary storage pest of sericulture
Scientific name: Dermestes ater
Order : Coleoptera
Family- Dermestidae
Period of occurrence:Throughout the year.
Life history of the pest
Life history of the pest
 Fecundity : 150-250
 Hatching: 3-6 days
 Larval duration: 28-40 days
 Pupal duration : 7-8 days
 Total life cycle: 38-54 days

21. Damage symptoms
 The grubs cause more damage than adults.
 The infested cocoons (especially seed and stifled cocoons) show the
presence of multiple irregular holes on them.
They do attack the green cocoons as well as the egg laying moths
 They do attack the green cocoons as well as the egg laying moths
whenever their population gets increased
 The estimated damage level due to the beetle attack to the pupae is
16.62% and moth 3.57% with 20.19% reduction in egg production in
grainages, especially those coming under government sector

22. Management of dermestid beetle
1. Mechanical: Collect the grubs and adults either by sweeping or by using a vacuum cleaner
and destroy them by burning or dipping in soap solution.
2) Physical: Exposure of beetle infested (grubs and adults) pierced / stifled cocoons packed
in HDPE (black) bags to sunlight for a period of 6 hours.
in HDPE (black) bags to sunlight for a period of 6 hours.
3) Chemical
 Wooden articles of the cocoon storage room and grainage should be dipped in 0.2%
Malathion solution for 2-3 minutes. After 10 days, the trays should be thoroughly washed
in water and sun dried for 2-3 days before reusing.
 Store pierced cocoons in Deltamethrin treated bags (bags soaked in 0.028% Deltamethrin
solution and dried in shade).

23. Management strategies
• The effective management of storage pests may be ensured by drying the
grains properly before storage, storing new grains in the clean godowns or
receptacles and plugging all cracks, crevices and holes in the godowns
thoroughly.
If infestation of grain has already taken place, then application of chemicals
• If infestation of grain has already taken place, then application of chemicals
becomes necessary.
 Surface treatment
 Seed treatment
 Fumigation

24.  Surface treament
• Disinfect old gunny bags by dipping them in 0.0125% fenvalerate 20EC or
cypermethrin 25EC for 10 minutes and drying them in shade before filling with
grains or use new gunny bags.
• Disinfect empty godowns or receptacles by spraying 0.05% malathion emulsion
• Disinfect empty godowns or receptacles by spraying 0.05% malathion emulsion
on the floor, walls and ceiling.
 Seed treatment
 Mixing of malathion 5% @of 250g /quintal of seed is recommended.
 Against pulse beetle cover the pulses stored in bulk with 7 cm layer of
sand or sawdust or dung ash.

25.  Fumigation
 Mixture of ethylene dichloride and carbon tetrachloride @ of 1L for 20
quintals of grain or 35L/100 m3 of space with exposure period of 4 days
is recommended. Methyl bromide is used at the rate of 3.5 kg per 100 m3
is recommended. Methyl bromide is used at the rate of 3.5 kg per 100 m3
of space with 10-12 hours exposure.
 The fumigant, hydrogen phosphide (aluminium phosphide), is available in
tablet form and can be used @ of one tablet (3 g) per metric tonne or 25
tablets /100 m3 of space with an exposure period of 7 days.

26. Integrated management of storage pest
The control methods of stored produce pests can be categorized into preventive and curative measures.
i)Preventive measures
• Brush the cracks, crevices and corners to remove all debris in the godown. Clean the machines like harvester
and thresher before their use.Made the trucks, trolleys or bullock carts free from infestation.
• Clean the godowns/ storage structures before storing the newly harvested crop to eliminate various bio
stages of pest hiding.
• Provide a metal sheet upto a height of 25 cm at the bottom of the wood in doors to arrest the entry of rats.
• Remove and destroy dirt, rubbish, sweepings and webbings etc from the stores.
• Close all the rat burrows found in godown with a mixture of broken glass pieces and mud plastered with
mud/ cement.
• Plaster the cracks, crevices, holes found on walls, and floors with mud or cement and white wash the stores
before storing of grains etc..

27. ii) Physical methods
 Provide a super heating system by infrared heaters in the floor mills and food
processing plants to obtain effective control of pests since mostly the stored
produce insects die at 55 –60˚ C in 10 – 20 minutes.
 Modify the storage atmosphere to generate low oxygen (2.4%) and to develop
 Modify the storage atmosphere to generate low oxygen (2.4%) and to develop
high carbon dioxide (9.0 – 9.5) by adding CO2 to control the insects.
iii) Cultural methods
 Store the food grains in air tight sealed structures to prevent the infestation
by insects.

28. iv) Mechanical methods
 Sieve and remove all broken grains to eliminate the condition which favour storage
pests.
 Stitch all torn out bags before filling the grains.
v) Chemical methods
 Treat the walls, and ceilings of empty godown with malathion 50 EC 10 ml/L.
 Spray malathion 50 EC 10 ml/ L with @ 3 L of spray fluid / 100 m2 over the bags.
 Use seed protectants like pyrethrum dust, carbaryl dust to mix with grains meant for seed
purposes only.

29. Summary
 A storage pest is an insect or other animal that damages or destroys
stored food or other stored valuable organic matter.
 Storage pests often go unnoticed because they infest items that are not
regularly used and they may be very small in size.
 Infestations are noticed when the pests emerge from storage, to disperse
 Infestations are noticed when the pests emerge from storage, to disperse
or sometimes as a result of crowding or after having exhausted a particular
food source, and search for new sources of food and harbourage.
 Storage pests are classified into primary and secondary pests. Secondary
pests are saw toothed grain beetles, long horned grain beetles, grain mite
etc..

30.  The effective management of storage pests may be ensured by drying
the grains properly before storage, storing new grains in the clean
godowns or receptacles and plugging all cracks, crevices and holes in the
godowns thoroughly. If infestation of grain has already taken place, then
godowns thoroughly. If infestation of grain has already taken place, then
application of chemicals becomes necessary.
 The control methods of stored produce pests can be categorized into
preventive and curative measures.

31. References
 https://agritech.tnau.ac.in/crop_protection/crop_prot_cro
p_sto_insect.html
 http://courseware.cutm.ac.in/wp-
content/uploads/2020/06/GADGETS-ENGLISH.pdf
 https://www.researchgate.net/figure/a-Indicator-device-b-
 https://www.researchgate.net/figure/a-Indicator-device-b-
TNAU-automatic-insect-removal-bin-c-Insect-Egg-
Removal_fig1_326268587